Sewing-machine



G. P. HARLOW. Sewing Machine.

No. 231,568. Patented Aug. 24, 1880.

UNITED STATES PATENT OFFICE.

OHARLES F. HARLOW, OF BOSTON, MASSACHUSETTS.

SEWING-MACHINE.

SPECIFICATION forming part of Letters Patent No. 231,568, dated August24, 1880.

Application filed August 18, 1879.

T 0 all whom it may concern:

Be it known that I, OHARLEs F. HARLOW, of Boston, Massachusetts, haveinvented certain Improvements in Sewing-Machines; and I do herebydeclare that the same are fully described in the following specificationand illustrated in the accompanying drawings.

The object of my improvements is to simplify and cheapeusewing-machines, and to render their operation more satisfactory thanthose heretofore used.

My improvements relate to the shuttle mechanism and to the means foractuating and regulating the feed apparatus.

My invention consists in the devices and combinations of devices setforth in the appended claims.

In the drawings, Figure 1 is a plan of the under side of the bed-plateof my sewing-machine with the mechanism attached thereto. Fig. 2 is avertical section of the inverted machine on line 00 as of Fig. 1; andFig. 3 is atop view of the eccentric and cam, right side up, with thebed-plate removed, showing the essential shape of the cam-groove.

A is the bed-plate of the machine, and a a curved rib formed integraltherewith and project-ing vertically downward, so as to form an uprightwall for the outer face of the shuttle to bear against as it vibrates ina short are.

B is a shaft passing vertically through the bed-plate, and having motionimparted to it in any suitable manner.

0 is a cam-wheel secured upon the shaft B, and having in its horizontalupper or lower surface a recess or groove of the form indicated in Figs.1 and 8 of the drawings, for the purpose of giving the required movementto the shuttle, and also of allowing it a certain period of rest equalto and corresponding exactly with the time occupied by the needle informing the loop through which the shuttle passes.

D is the shuttle-lever, bent or formed with an elbow and pivoted to thetable at E, and engaging by a stud or sleeve at one end with the grooveof the cam 0, while at the other end a cradle, d, is formed, open at thetop for insertion of the shuttle, and on the outer side toward thecurved wall a to permit the shuttle to bear against the said wall, butsupporting or carrying the shuttleby means of the bottom and ends ofsaid cradle as the lever is vi brated back and forth with everyrevolution of the cam O. The shuttle being carried in the cradle cl issubject to friction only against the vertical wall of the rib a, and norace is required in which it would otherwise be driven forward and backwith friction on two or three of its sides.

The shaft B also bears an eccentric, G, which is embraced by a strap atthe end of a lever, H, which lever passes between the knife-edges of afulcrum-block, l. with a screw passing through a slot in the table A,and wit-h a nut, J, by means of which its position may be varied at willor fixed permanently.

The lever H, having a suitable hearing, it, is formed with a bend oroffset, H, which passes diagonally through the feed-bar K, bearing theroughened feed-surface K, and the feed-bar is provided at its other endwith a short slot, through which its pivot passes.

From this construction of the parts it follows that rotation of theeccentric G will actuate the bent lever H and thefeed-bar, thelip-anddown movement of the feed-surface being due to the reciprocationback and forth of the bend or ofi'set H through the feed-bar K, whilethe forward-and-back movement of the feedsurface is produced by thelever H playing freely through the fulcrum I. In this simple manner Igive to the feed-surface K four positive m0tionsup, forward, down, andbackwithout any spring action.

The rapidity of the feed, and consequently the length of the stitch, isregulated by adjustment of the fulcrum-block by means of the nut J orotherwise.

I usually provide the fulcrum with a long slide-bar, I, with which theclamp-screw engages, so that the nut J may not be in the way of theoperator in using the machine.

The fulcrum-block may be merely slotted to receive a pin projecting fromthe lever H, or it may be swiveled to permit the desired movement of thelever.

The movement of the fulcrum itself is upon a rod, L, parallel to thetable A and lever H, whereby milling a path for it on the under side ofthe bed-plate is avoided. The rod L is This block is provided mounted inbrackets or proiections beneath the bed-plate A, or its ends may be bentand inserted in holes in the table.

This simple contrivance effects a material saving in labor, the rod Lbeing of ordinary round iron, and passing through a hole drilled ofproper size in the block I, instead of which the usual method is to millfour sides of an angular bar and the corresponding faces of the ways forsuch bar.

1 do not deem it necessary to describe in detail the parts of asewing-machine not shown in the drawings, since it is obvious they maybe of ordinary construction and arranged in any manner adapted to therequirements of shlittle-machines, and that variations therein would notmaterially affect the operation of my im u'ovements.

I claim as of my invention-- 1. The shuttle-driving mechanismhereindescribed, consisting of a single bent lever, I), of the firstclass, pivoted to the under side of the bed-plate, and having a cradle,II, at one end to receive the shuttle, in combination with a verticaldriving-shaft and a horizontal camwheel thereon, provided with a groovehaving a convex curvature, flattened on one side, as shown, with whichgroove the lever l) engages by means of a stud or roller thereon at theend opposite the shuttle, substantially as set forth.

2. The feed mechanism herein described, consisting, of an eccentricmounted upon a vertical shaft and a vibrating lever provided at one endwith an eccentric strap to engage with said eccentric, and at the otherend formed with a bend or offset, H", in combination with arough-surface feed-block mounted on a feed bar, K, having a perforationthrough which the offset II reciprocates, and a sliding fulerum, I, madeadjustable to and from the. feedbar, whereby the four motions of thefeedblock are all made positive and the length of the stitch isregulated, substantially as set forth.

3. The variable fulcrum herein described, formed of a block madeadjustable by means of a slot and screw, and arranged to slide back andforth upon a guide-rod, L, substantially as set forth.

4. In a shuttle sewing-machine of otherwise suitable construction, afeed-bar and a bent feed-lever, ll, having a sliding fulcrum, thevertical shaft B, and eccentric G thereon, as described, in combinationwith a shuttle-lever of the first order and a grooved cam-wheel, (J, onsaid shat't B, substantially as set forth.

CHARLES F. HARLOW.

Witnesses:

WM. P. BARKER, A. H. SPENCER.

